A transport apparatus for transporting radiation shielding members and an operator cab structure for this transport apparatus (see, for example, Patent Document 1), and a vehicle (car) with a retrofitted radiation protection device and a vehicle interior structure for this vehicle (see, for example, Patent Document 2) are known as examples of a manned vehicle for special environment use and a cabin structure for this vehicle.
According to FIG. 2 of Patent Document 1, the transport apparatus 5 is configured to run on continuous tracks 8, with an operator cab 9 surrounded by radiation shield plates provided on the continuous tracks 8.
According to FIG. 1 and FIG. 2 of Patent Document 2, the vehicle body 1 has a windshield part 2a covered by a first shielding member 3 and side parts 4 covered by second shielding members 20.    Patent Document 1: Japanese Patent Application Laid-open No. 2001-289990    Patent Document 2: Japanese Patent No. 4268162
Patent Document 1 does not describe in detail the structure of attaching the operator cab 9 on the continuous tracks 8. Substantial alteration may be needed if the shielding capabilities of the operator cab 9 are to be changed in accordance with the level of radiation exposure in the environment, which will increase the cost.
According to Patent Document 2, shielding members are attached to a common vehicle (car), but it would be difficult to cover the entire vehicle completely with shielding members. With no precaution against possible ingress of fine particles of special substances into the vehicle interior, it would also be difficult to provide sufficient countermeasures against special substances.